Controlling mechanism for motors



June 27, 1933. w. C. POWELL 1,915,760

VCONTROLLING MECHANISM FOR MOTORS Filed June 11, 195o 2 sheets-sheet 1 b VWL/.ARD C. POWEZL. ,M

mls ATToR/VEY June 27, 1933. l wl c'. POWELL 1,915,760

CO'NTROLLING MECHANISM FOR MOTORS Filed June l1, 1950 2 Sheets-Sheet 2 T0 MOTOR /N VEN TOF?.

/7/'5 ATTORNEY b WILL/)HD C. POWELL,

Patented June 27, 1933 UNITED s'riirl'ezsy APATENT oFFlcE WILLARD C. POWELL, OF DAYTON, OHIO, ASSIGNOR T OSCAR BI. POOCK, DOING BUSI- NESS AS THE CITY MACHINEEG TOOL WORKS, 0F DAYTON, OHIO CONTROLLING MECHANISM FOR MOTORS Application filed .Tune 11,

This invention relates to a controlling mechanism for automatically reversing the direction of operation of an electric motor and is designed more particularly for use in connection with a gear polishing machine of the type shown and described in the application for patent filed by Thomas J. Mullen and Villard C. Powell on April 28, 1930, Serial No. 448,077. The machine shown and described in that application comprised a rot-ary polishing element which was rotated in contact with the gear to be polished first in one direction and then in the opposite direction. The polishing element was driven from a reversible electric motor and means were provided for automatically reversing the direction of operation of the motor after the polishing element had made a predetermined number of revolutions in one direction and for interrupting the operation of the motor afterthe polishing eement has made a predetermined number of revolutions in the opposite direction. The motor controlling mechanism was not wholly satisfactory, primarily because it required the use of a switch having'three positions, a forward position, a reverse position and a neutral position. y

One object of the present invention is to provide simple and efficient means for automatically controlling the direction of operation of an electric motor.

A further object of the invention is to provide such a controlling mechanism comprising; a master switch having two positions only. i

A further object of the invention is to provide such a mechanism in which the'cycle of operations may be initiated by operating a push button, or like switch, and thereafter the cycle of operations will be completed and terminated automatically.

Other objects of the invention will appear as the mechanism is described in detail.

i vice; Fig. 3 is a sectional view of the revers- 1.930. seriai No.`4eo,532.

ing device; Fig. 4 is a plan view of the master switch and its actuating mechanism; F ig. 5 is a side elevation of the switch actuating mechanism; Fig. 6 is a detail view of the master switch; and Fig. 7 is a diagram of the circuits.

In these drawings I have illustrated one embodiment of my invention and have shown the same in connection with a gear polishing machine of the type shown in the above mentioned application but it will be understood that the invention may take various forms and may be employed in connection with motors used for various purposes.

The machine here illustrated comprises a polishing element 10 rotatable about a vertical axis and two other-polishing elements 11 mounted for4 bodily movement toward and from the first mentioned polishing element, the several polishing elements being arranged to receive a gear between them and to act simultaneously thereon. The gears are fed to the polishing elements by means of a conveyor 12.v Neither the conveyor 12 nor the means for operating the polishing elements 11 are involved in the present inventionY and they need not be described in detail. The polishing element 10 is mounted on the lower end of a vertical shaft 13 to which is secured a worm gear 14 which meshes with a worm 15 on a shaft 16. v rllhis shaft is driven from a reversible electric motor 17 which, in the present instance, is connected with the shaft 16 by a belt 18. The shafts 13 and 16 and their associated gearing are enclosed in a housing 19. In operation the polishing element 10 is irst rotated through a predetermined number of revolutions in one direction, the motor is then reversed and the polishing element rotated through a predetermined number of revolutions in the opposite direction, and the motor is then stopped to permit the polished gear to be removed and another gear placed in operative relation to the polishing elements. The construction and operation of the machine, apart from the motor controlling mechanism, is substantially the same as that shown and described in the above mentioned application- The reversal of operation of the motor is effected by the manipulation of motor switches 20 and 21, which are of a well known type and need not be here described in detail. The motor switches are magnetically operated and, as here shown, the switch 20 is connected withl the core of a solenoid 22 and the switch 2l is connected with the core of a sclenoid 23. The solenoids are separately energized to` alternately close Ythe switches, each switch moving automatically to its openposition when its magnet is deenergized. The windings of the two magnets are connected to one side of the motor circuit, as shown at 24, and the magnet circuits are controlled by a--master swit-ch which comprises two fixed contact members 25 and 26, the xed contact member 25 being connected by conductor 27, switch 28 and conductor 29 with the winding of the magnet 22 and the fixed contact member 26 being connected by a conductor 30fwith the winding of the magnet 23. A movable switch member 31k is connected by a conductor 32 with a motor circuit and is movable into contact with either of the fixed Contact members. Normally the movable Contact member is in Contact with the fixed contact member 25. The switch 28 which is interposed between the fixed contact member 25 and its magnet V22 is normally open and comprises a movable member 33 which is operatively connected with the magnet so that it will be moved toits closed position'when the magnet lis energized. In the present instance, the

motor circuit, in the present instance by con nccting the same with the conductor 27. The closing of the push button or switch 34 will close the circuit through the magnet 22, thereby venergizing the same, closing the motorswitch 20 to cause the motor to operate and closing the switch 28 to connect the'magnet with the master switch. This operation takes place instantly upon the pressing of the switch butt-on and the latter may be im-v mediatelyV released as the switch 28 will remain closed so long as the magnet is energized.: After a predetermined interval the movable contact member 31 of the master switch is'actuated by motor controlled mechanism, to be hereinafter described, to move the same out of contact with the fixed contact member 25 and into contact with the fixed contact member 26, thus deenergizing the magnet 22 and permitting the motor switch 20 to open and also permitting the switch 28 in the magnet circuit to open, and closing the circuit through the magnet 23, thereby energizing that magnet and closing the motor and the motor will stop and remain idle until the push but-ton is again operated.

The movable switch member 31 may be actuated in any suitable manner. As here shown, it is rigidly secured to a shaft 35 which is journaled in suitable bearings on a supporting bracket or housing 36. Rigidly secured to the shaft 35, at one side of the housing, is an actuating arm 37 which has f rocking movement about the axis of the shaft 35, this movement being limited by fixed stops 38 and 39. Rocking movement is fore, both motor switch-es will remain open c imparted to the actuating arm 37 `through a p suitable motor operated reversing device of such a character that it will cause the actuating arm t0 be lmoved first in one directionl and then in the other. As here shown, this motor operated "mechanism is mounted within a housing 40 and comprises a shaft 41 mounted in the wall of that housing and having on itslouter end a rock arm 42 which is operatively connected with the actuating arm 37 for the switch. Preferably the connection is of such a character that the actuatingarm will be moved from one position to the other with a snap action. As here shown, the arms 37 and 42 are substantially parallel and each has its free end adjacent to the axis ofthe other arm. The free ends of the two arms are connected one to the other by a coiledA spring 43 which is attached at its ends tol the respective arms. The arms are so arranged that when the actuatingy arm 37 is in contact with. one of its stops, the stop 38 as shown in Fig. 5, the arm 42 will have its free end located on one side-of the shaft 35 such a distance that the spring 43 will hold the arm 37 firmly in contact with its stop. When movement is imparted to the arm 42 about its axis the free end of the arm will move across the axis of the arm 37 but that arm will remain stationary `until the arm 42 has moved such a distance beyond the axis of thearm 37 that the pull of the spring 43 will shift the i arm 37, and the spring will then snap ythe arm 37 to its other position, in contact with the stop 39.

The moto-r operated mechanism for imparting movement to the arms 42 and'37 may take various forms but I have here employed the same type of mechanism whichis shown and described in the above'mentioned application. As here shown, a shaft 44 eX- tends into the housing 19 and has at its inner end a worm wheel 45 which meshes with a worm 46 on the motor driven shaft 16. The outer end of this shaft extends into the housing 40 and has secured thereto, for rotation therewith, a disk 47. Rotatably mounted on the shaft and extending` loosely through the disk at the axis thereof, is a stud 48 which carries an arm 49 which is pivotally connected at its outer end to'a rock arm 50 rigidly secured to the inner end` ofthe shaft 41, which carries the rock arm 42. The arm 49 is slidably mounted on the stud 48 to permit it to accommodate itself to the changed positions of its pivotal connection with the rock arm 50. Projecting from the face `of the disk 47 are studs 51 and 52 which are arranged on opposite sides of the arm 49 and adapted to alternately engage and actuate that arm. Vhen the motor 17 is in operation the disk 47 will be rotated from the motor driven shaft 16. 'I'he gear ratios between the shaft 16 and the shaft 44 and between the shaft 16 and the vertical shaft 13 are such that the polishing element on the shaft 13 will make the desired number of revolutions while the disk 47 is making a partial revolution. As the disk rotates one of the studs, 51 or 52, will be moved into contact with the arm 49 and will move that arm about the axis of the stud 48 this movement being transmitted through the rock arm 50 andshaft 41 to the rock arm 42 which is operatively connected with the switch actuating arm las above described. Upon the operation of the switch the direction of rotation of the motor is reversed and the disk 47 is rotated in the opposite direction until the other of the studs, 51 or 52, engagesthe arm 49 and moves the same in the opposite direction to again actuate the switch.

lVhile I have shown and described one embodiment of my invention I wish it to be understood that I do not desire to be limited to the details thereof as various modiiications may occur to a person skilled in the art.

Having now fully described my invention, what I claim as new and desire to secure by Letters Patent, is

1. In acontrolling device for an electric motor comprising motor switches to control the direction of operation of said motor, and electro-magnets to actuate the respective motor switches; a master switch connected with both magnets to cause the same to be alternately energized and held normally in a position to close the circuit for one magnet at said master switch, means to initially energize the magnet whose circuitis normally closed at the master switch, other means to maintain said magnet energized so long as said master switch remains in its normal poition, and means controlled by the motor to actuate said master switch to deenergize said magnet after a predetermined operation of said motor in one direction and to immediately energize the other magnet.-

2. In a controlling devicefor an electric motor comprising motor switches to control the direction of operation of said motor, and electro-magnets to actuate the respective motor switches a master switch connected with both magnetsl to cause the same to be alternately energized and held normally in a position to close the circuit for one magnet at said master switch, means to initially energize the magnet whose circuit is normally closed at the master switch, other means to maintain said magnet energized so long as said master switch remains in its normal position, and means controlled by the motor to actuate said master switch to deenergize said magnet after a predetermined operation of said motor in one direction and to immediately energize the other magnet, and to subsequently restore said master switch to its normal position.

3. In a controlling device for an electric motor comprising motor switches to control :f

closed at the master switch, a starting switch connected in circuit with said magnet, adapted to be closed to initially energize said magnet and cause said magnet operated switch to be closed, and to be opened after said magnet operated switch is closed, and means controlled by the motor to actuate said master switch to break the circuit through the first mentioned magnet and through said magnet operated switch after a predetermined opera.- tion of the motor in one direction and to immediately close the circuit through the other magnet. y

' 4. In a controlling device for an electric motor, comprising motor switches to control y the direction of operation of said motor, and electro-magnets to actuate the respective motor switches; a master'switch connected with both magnets to cause the sameto be alternately energized and held normally in a position to close the circuit of one of said magnets at the master switch, -a magnet operated switch interposed between said master switch and that magnet whose circuit is normally closed at the master switch,v a starting switch connected in circuit with said magnet, adaptlio ed to be closed to initially energize said magnet and ycause said magnet operated switch to be closed, and to be opened after said magnet operated switch is closed, and means controlled by the motor to actuate said master switclitobreak the circuit through the first mentioned magnet and through said magnet operated switch after a predetermined operation of the motor in one direction, to vimmediately close the circuit through the other magnet, and to thenbreak the circuit through the last mentioned magnet and restore the master switch to its normal position.

5. In a controlling device for an electric motor comprising motor switches to reverse the direction of operation of said motor, and electro-magnets toA actuate the respective inotor switches; a master switch having two fixed contact members and a movable contact member, means for connecting said movable contact member with a source of electric current, means for connecting said magnets with a source of current and with the respective fixed contact members, said movable contact member being normally in Contact with one of said fixed Contact meinbers, a normally open switch interposed between the last mentioned fixed Contact member and its magnet, means for closing the last mentioned switchwhen said magnet is energized, means for initially energizing said magnet, and means controlled by the motor for quickly moving the movable member of said master switch from said last mentioned fixed contact member to the other fixed Contact member and thereby instantly reversing the motor.

6. In a controlling device for an electric motor comprising motor switches to reverse the direction of operation of said motor, and electro-magnets to actuate the respective motor switches gl a master switch having two fixed Contact members and a movable contact member, means for connecting said movable contact member with a source of electric current, means for connecting said magnets with a source of current and with the respective fixed Contact members, said movable contact member being normally in contact with one of said fixed contact members,

a normally open switch interposed between the last mentioned fixed contact member and its magnet, means `for closing the last mentioned switch when said magnet is energized, meanscomprising an automatically opening manually operated switch for closing the circuit through f said magnet independently of thenormally open switch, and means controlled by the motor to move said vmovable contact member from its normal pomotor, comprising motor switches to reverse the direction of operation of said motor,

and electro-inagnets to actuate the respective motor switches, a master switch having two fixed. contact members connected with the respective magnets, and a movable contact member supported normally in contact with one of said fixed Contact members, a

normally open switch interposed between the last mentioned fixed contact member and its magnet and connected with said magnet for operation thereby, means comprising a manually operated switch to initiallyv energize said magnet and close the corresponding motor switch and the normally open switch, an actuating member operatively connected with said movable contact member, and a device operated by the motor to move said actuating member first in one direction and then in the other direction at predetermined intervals. c

8. In a controlling device for jan electric motor comprising motor switches to reverse the direction of voperation of said motor, and electro-magnets to actuate the respective motor switches; a master switch having two fixed contact members connected with the respective magnets, and a movable contact member supported normally in contact with one of said fixed contact members, a normally open switch interposed between the last mentioned fixed contact member and its magnet and connected with said magnet for other direction at predetermined intervals, and means to cause said actuating member to move from one snap action.

9. In a controlling device for an electric motor comprising motor switches to'reverse the direction of operation of said motor, and electro-magnets tol actuate the respective motor switches; a master switch having two fixed contact members connected with the respective magnets, and a movable contact member supported normally in contact with one of said fixed contact members, a normally open switch interposed between the last mentioned fixed contact member and its magnet and connected with said magnetl for operation thereby, means comprising a manually operated switch to initially energize said magnet and close the corresponding motor switch and the normally open switch, an actuating arm operatively connected with position to the other with -a said movable Contact member, a rock arm mounted adjacent to said actuating arm, a device operated by the motor to move said rock arm first in one direction and then in the other direction, and means for operatively connecting said arms one with the other.

l0. In a controlling device for an electric motor comprising motor switches to reverse the direction of operation of said motor, and electro-magnets to actuate the respective motor switches; a master switch having two fixed contact members connected with the respective magnets, and a movable Contact member supported normally in contact with one of said iixed Contact members, a normally open switch interposed between the last mentioned fixed Contact member and its magnet `the free ends or" said rock arms one to the other, and means operated by the motor for moving said second rock arm first in one direction and then in the other direction.

In testimony whereof, 1 affix my signature hereto.

WILLARD C. POWELL. 

